Democracies are indeed slow to make war, but once embarked upon a martial venture are equally slow to make peace and reluctant to make a tolerable, rather than a vindictive, peace.
Reinhold Niebuhr: Major Works on Religion and Politics (LOA #263): Leaves from the Notebook of a Tamed Cynic / Moral Man and Immoral Society / The Children ... History (Library of America (Hardcover))